A United Nations-appointed mission to Libya has said there are “probable mass graves” yet to be investigated, possibly as many as 100, in a town where hundreds of bodies have already been found.

The report to be submitted to the UN Human Rights Council this week details how fighters from the Kaniyat militia executed and imprisoned hundreds of people between 2016 and 2020, sometimes keeping them in tiny oven-like structures called “the boxes”, which were set alight during interrogations.

The evidence of kidnappings, murder and torture in Tarhuna, uncovered by the independent fact-finding mission, represents one of the most egregious examples of rights abuses in the turbulent period since Muammar Gaddafi’s removal in 2011.

Among the victims were disabled people, as well as women and children, the 51-page report said.

Based on the testimonies of residents and two site visits, the mission found “reasonable grounds” that the Kaniyat militia committed crimes against humanity. It identified four commanders who participated directly in them.

Libyan authorities have already recovered 247 bodies in mass and individual grave sites in the Tarhuna area in western Libya. Many of the victims were still handcuffed and blindfolded.

The mission used satellite imagery showing signs of soil disturbances among other evidence to identify three new likely sites. But there could be many more, it said, citing an existing grave known as “The Landfill” where just a tiny fraction of the site has been investigated.

“According to insider knowledge, there might still be up to 100 as of yet undiscovered mass graves,” the report said.

It is not immediately clear how the findings will reflect on Libyan authorities. Libya’s diplomatic mission in Geneva has not made a statement about the issue.

Allied with both governments

At one stage, the Kaniyat was aligned with the Tripoli-based Government of National Accord but later with the eastern Libyan National Army, led by General Khalifa Haftar that tried, unsuccessfully, to overthrow the internationally recognised National Accord administration. The fighters no longer hold authority in Tarhuna.

The surviving leaders of the Kaniyat are mostly believed to have fled to areas of eastern Libya under Haftar’s control.

In its conclusions, the fact-finding mission (FFM) calls on Libyan authorities to continue searching for the graves. It also urges them to establish a special tribunal to prosecute international crimes.

Tracy Robinson, one of the three heads in charge of the 18-person team, said it did not have the resources or authority to investigate the Tarhuna graves alone. “It’s the state’s duty to act,” she told journalists in Geneva.

The report refers to difficulties with the cooperation of Libyan authorities in the past. Diplomats and UN sources told Reuters that Libya had previously expressed reservations about continuing the mission, which expires this month.

A resolution is currently before the Geneva-based council to keep investigations going for another nine months, which is less than some had hoped for.

A decision is expected this week and, if successful, FFM members said they intend to submit further evidence, a final report and a confidential list of individual suspects to the council next year.